我试图做某种“随机发生器”——有几个相邻的点，根据它们的亮度，它们或多或少有可能被选中。
一个点是一个具有坐标和x值的对象，存储它的亮度。yb
我的方法是设置一个具有 a和一个值（介于 0 和 1 之间）的p对象（用于可能性） -和值之间的差异取决于它们的亮度。pstartendstartend
然后我生成一个随机数并遍历所有点以查看随机数是否在它们start和end属性之间。由于一个点start值是前一个点的end值，因此只应选择一个点，而是选择随机数量的点。
因此，我记录了随机值以及点start和end属性。看起来一切正常，除了以下代码
for (i = 0; i < numAdjacentPoints; i++) {
// set some shorthands
curr_point = adjacentPoints[i];
// if there is no previous point, we start with 0
prev_point = ((i === 0) ? {p: {end: 0}} : adjacentPoints[i-1]);
// initiate a probability object
curr_point.p = {};
// set a start value (the start value is the previous point's end value)
curr_point.p.start = prev_point.p.end;
// set an end value (the start value + the point's brightness' share of totalBrightness)
// -> points with higher darkness (255-b) are more have a higher share -> higher probability to get grown on
curr_point.p.end = curr_point.p.start + (255 - curr_point.b) / totalBrightness;
// if the random value is between the current point's p values, it gets grown on
if (curr_point.p.start < rand < curr_point.p.end) {
// add the new point to the path array
path[path.length] = curr_point;
// set the point's brightness to white -> it won't come into range any more
curr_point.b = 255;
console.log(" we've got a winner! new point is at "+curr_point.x+":"+curr_point.y);
console.log(" "+curr_point.p.start.toFixed(2)+" < "+rand.toFixed(2)+" < "+curr_point.p.end.toFixed(2));
}
};
输出这个：
we've got a winner! new point is at 300:132 mycelium.php:269
0.56 < 0.53 < 0.67 mycelium.php:270
we've got a winner! new point is at 301:130 mycelium.php:269
0.67 < 0.53 < 0.78 mycelium.php:270
we've got a winner! new point is at 301:131 mycelium.php:269
0.78 < 0.53 < 0.89 mycelium.php:270
we've got a winner! new point is at 301:132 mycelium.php:269
0.89 < 0.53 < 1.00
--> 怎么回事？0.56 < 0.53 < 0.67??